Rotary air-compressor



J. 0. CARREY.

' ROTARY AIR COMPRESSOR.

APPLICATION FILED DEC.22, 1919.

1,37 9,248. Patented May 24, 1921.

Z 2 SHEETS-SHEET I.

I. 0. CARREY.

ROTARY AIR COMPRESSOR.

APPLICATION FILED DEc.22, |919.

Patented May 24.. 1921.

Uien STATES PATENT ricerca.'

.TOEN 0. CARREY, OF ST. LOUIS, MISSOURI, ASSIGNOR TO CARRYROTARY ENGINE COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION OF MISSOURI.

ROTARY AIR-COMPRESSOR.

Leraars.

Specication of Letters Patent.

Application filed December 22, 1919. Serial No. 346,575.

full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawv ings, forming part of this specification.

ly invention relates to an air or fluid compressor, the principal objects of my invention being to generally improve upon and simplify the construction of the existing and generally used forms of fluid compressors, and to provide a relatively simple and easily operated structure which may be effectively and economically used wherever it is desired to rapidly compress to a relatively high degree of pressure, air, gas, or

l other iuids.

Further objects of my invention are to provide an improved and eiicient seal or liquid packing between the fixed and mov-` able parts of the compressor so as to minimize the leaka e of fluid from the compressor, and, urther, to provide simple means for continuously lubricating the operating parts'of the apparatus.

My invention i's ,characterized by the arrangement of a pair of rotors within a housing, said rotors having interengaging partsy one of the'heads or side plates thereof removed. y 0 Fig. 2 is a vertical section taken approximately on the line 2-2 of Fig. 1. Fig. 3 is a sectional view taken approximately on the line 3 3 of Fig. 2. Fig. 4. is a vertical section taken approximately on the line 4-4 of Fig. 2.

"Fi 5 is a detail section takenapproximately on the line 5-5 of F1 1. l

Referring by numerals to t e accompanying drawings which illustrate a practical embodiment of myV invention, 10 designates a .ring which forms the annular wall of the housing of -the compressor and applied to the sides of said ringvand secured thereto in -any suitable manner are disk-shaped heads 11 and 12 which coperate with the ring 10 in forming the housing.

Formed integral with the heads 11 and 12 are centrally arranged outwardly projecting tubular members 13 within which are arranged bushings 14 that serve as bearings for the driving shaft 15 of the compressor.

Removably positioned on the outer end of the tubular member 13 that projects from head 12 is an imperforate cap '16, the space 17 within which rforms a liquid lubricant chamber. Removably positioned on the tubular member 13 that projects from head 11 is a cap 18 in the center of which is formed an aperture for the accommodation of shaft,

15, and arranged in the chamber within this cap 18 is a suitable packing ring 19 which is effective in preventing the leakage of liquid lubricant outwardly along the surface of the shaft 15 and through the aperture in said Patented May 24, 1921.

cap 18. Either one or both of the heads 11 and 12 may be provided with a bracketsuch as 20and which latter may be xed toa suitable supporting base 21.

Formed through the upper portion of the* ring 10 is a transversely disposed port 22, and tapped into the ring and leading from this port to a suitable compressed fluid container (not shown) is a pipe 23. Formed in the upper portions of the heads 11 and 12 are vertically disposed ports 24,. the upper y ends ofv which communicate with the transverse port 22, and they lower ends communi- Zcating with the rotor chamber within the housing.-

Fitting snugly within the housing Aring 10 is a bearing ring 25 and' positioned therein. with `its outer circumference or periphery bearing against the inner face of said ring 25 is the annular rotor 26 of the compressor.

The inner periphery of this annular rotoris provided'with teeth 27, either straight or of the herring-bone type'.

j Rigidly fixed upon shaft 18 and disposed within the annular rotor 26 is the inner rotor` 28 of the compressor, said inner rotor being provided on its periphery with teeth 29 which mesh with the internal teeth 27 on ring 26. The parts just described are constructed so that the inner rotor 26 is eccentricall disposed 4withinthe' annular rotor 26 an the arrangement is such that the point where the teeth of the two rotors-en-l gage to the greatest depth is in the same plane with the lower ends of the ports 24, and such point obviously -being the point of hi 'hest compression in the compressor. ositioned within the space between the two rotors isfa crescent shaped filler block 30, the inner radius of which corresponds to the radius of the internal rotor 28 so that the outer faces of the teeth 29 ride directly against said inner radius and the outer or external radius of said block corresponding to the inner radius of the rotor 26 so that the inner faces of the teeth 27 bear directly against the outer radius or face of said block.

One end of the filler block 3G terminates in a plane slightly below `the horizontal plane occupied by the axis of shaft 15 and formed through head 12 immediately above this end. of the filler block is an aperturel which admits the air or other fluid that isto be compresse'd. This inlet aperture communicates with an arcuate recess 32, which latter extends upwardly toward the point of high compression between therrotors land being for the purpose of admitting -air or other Huid to the'spaces between the inter en aging teeth of the rotors.

he means utilized for lubricating the ,compressor and for roviding a liquid seal between certain of t e operating -parts includes an oil supply lpipe 33 that leads from a suitable oil separator (notl shown) and through which separator passes the air'or fluid that is compressed in the apparatus.

Obviously the oil from thisioil separator is under pressure and it passes through supply pipe 33 into one end `of an arcuate.

groove 34 thatis formed in the inner face of head 12.y This groove is concentric with and disposed vertically below the axis of shaft 15 and its upper end terminates a short distance from the lower end of the corresponding port 24. (See Fig.'3). This arcuate groove is disposed so that it bridges the space and establishes communication between the inner and outer portions of the radially disposed liquid sealing grooves 35 that areN formed in lthe corresponding side face .of the vinternal rotor 28. There is a pair of these grooves for each tooth of the internal rotor and the inner ends ofll the inner portions of said grooves communicate "with transversely disposed .apertures 36 that are formed through the body of the internal rotor. The outer ends of thel outer portions of'said grooves terminater at the outer face side faces are lprovided with substantially semi-circular concentric liquid sealing Y just mentioned will become filled with oil under pressure, and as a result, the moving parts of the apparatus will be thoroughly lubricated and at the samevtime an effective seal will be provided to minimize leakage of air from the compressor.

In order to provide for the lubrication of the bearings for the shafts 15 in the heads 11 and 12, a radially'disposed duct 39 extends fromone of the transverse apertures 36 in the internal rotor to an axially disposed' duct 40, that is formed in shaft 15, and which extends from the end of the shaft that terminates in cap 16 to a point beyond the internal rotor and in the last mentioned point, this axially dis osed duct communicates with a short radially disposed du'ct 41 that leads to the exterior of that portion of shaft 15 that is journaled in the bearing on head 11.

By virtue of this construction, oil under pressurev passes from the transverse vaperture 36 through the radial duct 39 and from thence through duct 40 and radial duct 41. Thus the inner surface of the bushing 14 in the head 11 is lubricated and the oil from chamber 17 delivered through duct 40 will pass' into the bearing between the end of the shaft of the bushing in head 12.

Any leakage of oil outwardly past the immediately above the path of travel of the teeth 29 on the internal rotor. (See Fig. 2.)

Formed in the inner face of. head 11 and disposed concentric with and generally below the shaft 15 is a substantially semi-cir cular groove or recess 43 that is arranged so thatit communicates directly with the ends of the transverse apertures 36 in the internal rotor, such construction providing forthe distribution of oil onto the inner face of head 11. l

. f The operation of my improved fluid compressor is as follows: l

, Shaft 15 carrying the internal rotor 28 is rotated at the proper speed in the direction indicated by the arrow in Fig. 1, and the teeth or projections on the periphery of said internal rotor engaging with the internal teeth on the external rotor drives the latter at the same speed and in the same direction. Air is drawn into the rotor chamber through inlet opening 31 and passes from thence into recess 32, and in the adjacent spaces between the teeth or interengaging projections of the rotors. The air thus drawn into the compressor is carried around to the opposite side of the rotor chamber and in so doing it travels above and below the crescent-shaped iller block 30.

The teeth or interengaging portions of the rotors mesh or engage with each other in progressivemanner after leaving the end of the filler block 30, thus gradually diminishing the area of the spaces between said teeth until the point of highest` compression is reached, whereupon the compressed air or fluid willbe forced outwardly in opposite directions from between-the meshing teeth,

and after passing upwardly through thel ports 24,4 said compressed air or Huid will pass through the tubular connection 23 to the storage tank.

4 A rotary compressor of my improved construction is comparatively simple, comprises but few operating parts, 'can be driven with' the expenditure of comparatively little power, and is capable of producing relatively high degrees of fluid pressure. y

Inasmuch as the oil delivered into the compressor through supply'pipe 33 is under pressure, said oil will be very thoroughly distributedthroughall the ducts, a ertures,

and pockets in the compressor, there y eii'ectively lubricating the operating parts of the compressor and providing a liquid seal to minimize the leakage of fluid pressure.

- It will be readily understood that minor changes in the size, Jform and construction of the various parts of my improved compressor can be made and substituted for those herein shown and described, without departing from the spirit of my invention, the scope of which is set forth in the appended claims.

I claim:

1. In a fluid compressor, the combination Y of an external rotor and an internal rotor, a casing surrounding said external rotor, heads on each side of said casing, and a separate bearing ring loosely mounted for rotation between the periphery of said external rot-or and said casing.

2. An internal rotor for a compressor of' the character described having separated lubricating grooves, in combination with a head having a lubricating groove or recess for forming a connection between the Vseparated grooves of the rotor in the course of the revolution of the latter.

3. A iuid compressor comprising a casing, heads on each side of said casing, an external rotor and an internal rotor mounted within the casing, the latter being provided with lubricating grooves and groove-com necting openings designed to coperate with lubricating grooves in said heads in the course of revolution of saidinternal rotor, and means for supplying a lubricant under pressure to one set of grooves whereby said lubricant is forced un er pressure through said groovesand openings to the low pressure side of the compressor.

In testimony whereof I hereunto affix my signature this 15th day of December, 1919.

` JOHN O. CARREY. 

